Definition
A course reversal maneuver in which the aircraft, after crossing a fix on the inbound course, turns 45° away from that course, flies straight for a set time (typically 40 seconds for Category A and B aircraft, or 60 seconds for Category C, D, and E aircraft), then makes a 180° turn in the opposite direction to intercept the inbound course.
Plain English
A way to turn the airplane around so it ends up flying back along the same line it came in on. The pilot angles off 45° to one side, holds that heading for a short time, then makes a steady turn the other way to roll out heading back the opposite direction on the original course.
Context Anchor
Seen on instrument approach charts and in FAA course-reversal guidance when a pilot must reverse direction before continuing inbound on an approach.
Derivation
The name describes the geometry: the initial offset from the inbound course is 45°. The full maneuver is built around that single defining angle, so the angle becomes the name.
Why Pilots Care
Keeps the aircraft inside protected airspace while reversing course, ensuring a safe and efficient transition onto the approach.
Intuition Check
Do not read this as any normal turn that happens to be 45 degrees. In this context, it is a specific published course-reversal pattern used to get established inbound on an instrument approach.
Example Sentence 1
After crossing the fix outbound, the pilot began the 45° procedure turn, held the offset heading for 40 seconds, then turned back to intercept the inbound course.
Example Sentence 2
The approach plate authorized either a 45° procedure turn or a holding pattern for course reversal.